The present invention relates to pipe patches or plugs and most specifically to a hydro seal, pipe patches or plugs for so called "deep tunnel" projects.
In a number of major cities in the United States the storm sewer system has proven inadequate in rain storms where a great deal of rain falls in a short period of time. In such a situation the ordinary municipal sewer system overflows and raw sewage can flow into the lakes or rivers where ordinarily only pure water is discharged after sewage treatment.
Certain cities have been required by court order to correct such a situation where it also affects the water supply for other communities downstream or on the same body of water.
One solution that is being tried in a number of major U.S. cities is to excavate one or more "deep tunnels" under the city to act as holding tanks or vats for such overflow when there is a need and then the contents can be lift pumped to the water treatment facility after the emergency situation is over.
When such a "deep tunnel" is excavated it usually is deep enough to be located in the underlying rock formations. In many areas the rock is sedimentary, but even igneous or metamorphic rock will have faults and fissures. When such is the case, and that is usual, there is the strong possibility that water may flow into the tunnel excavation in substantial quantities. This water is sometimes from a long way away flowing underground through the rock formations and sometimes is the water from the local water table. Aside from this problem being undesirable in the construction of the tunnel, there is also the problem that the outflow of water from the local water table can create "sink holes" or cause pilings supporting major buildings to start serious rotting or deterioration once the water is removed endangering buildings above the general area of the "sink holes" or the drained water table.
In the past the attempt was made to introduce a caulk into the fissures to plug the incoming water and cause it to flow undisturbed as it had in the past before the excavation. This did eventually solidify and plug the fault or fissure if the water flow could be temporarily stopped but it took a great deal of time to stop the flow with rags and other materials and for the caulk to